| EP0541145 | Monitoring system for monitoring a telecommunication network containing one or more subscriber exchanges. | |||
| WO/1997/057469 | ||||
| WO/1995/033352 | A SYSTEM FOR MONITORING TELEPHONE NETWORKS AND/OR DATA COMMUNICATION NETWORKS, ESPECIALLY MOBILE TELEPHONE NETWORKS | |||
| WO/1997/005749 | TELECOMMUNICATIONS CALL MANAGEMENT SYSTEM | |||
| WO/1998/047275 | SIGNALING NETWORK GATEWAY |
The present invention is related to pending applications assigned Ser. No. 09/057,940, entitled SYSTEM AND METHOD FOR MONITORING PERFORMANCE STATISTICS IN A COMMUNICATIONS NETWORK, filed Apr. 9, 1998; Ser. No. 09/092,428, entitled SYSTEM AND METHOD FOR DETECTING HIGH MESSAGE TRAFFIC LEVELS IN A COMMUNICATIONS NETWORK; Ser. No. 09/092,699, entitled SYSTEM AND METHOD FOR SIGNAL UNIT DATA STORAGE AND POST CAPTURE CALL TRACE IN A COMMUNICATIONS NETWORK; Ser. No. 09/092,256, entitled SYSTEM AND METHOD FOR GENERATING QUALITY OF SERVICE STATISTICS FOR AN INTERNATIONAL COMMUNICATIONS NETWORK; and Ser. No 09/092,771, entitled SYSTEM AND METHOD FOR CORRELATING TRANSACTION MESSAGES IN A COMMUNICATIONS NETWORK, all filed Jun. 5, 1998; and Ser. No. 09/093,824, entitled TRANSACTION CONTROL APPLICATION PART (TCAP) CALL DETAIL RECORD GENERATION IN A COMMUNICATIONS NETWORK, filed concurrently herewith. These applications are commonly assigned and are hereby incorporated by reference herein.
The present invention is related to monitoring signals in a communications network and, more particularly, to measuring service provider service quality on a communications network.
Common channel signaling networks, such as the Signaling System Seven (SS7) based signal system, use dedicated channels to pass digital messages between systems for call setup, call control, call routing, and other functions. These dedicated signaling channels are part of a network that is separate from the network that carries the actual voice and data signals. An SS7 network is a separate switching system which is used prior to, during, and at the end of an actual voice or data call. The SS7 network is used to route control information. Whenever two switches or elements have to pass call control information during or prior to a phone call, they pass this data via the SS7 signaling network.
There are three basic types of network node elements in an SS7 network. One of them is the Service Switching Point (SSP), which may be a central office switch, a tandem switch or an end office switch. A second principal node element is the Service Control Point (SCP). An SCP acts as a database query server for the rest of the network. An SCP is used in such applications as translating ported telephone numbers, routing 800 calls, tracking roamers in a cellular network, and Alternate Billing Service/Line Identification Database services (or ABS/LIDB) which provide operator-type services. The third principal node element is the Signal Transfer point (STP). An STP is essentially a packet switch that routes the messages from SSPs and SCPs to SSPs and SCPs.
It is possible to combine these three different types of nodes into a single node. However, in North America, they are typically not combined. An SSP performs only switch functions, an SCP only control functions, and an STP only signal transfer functions. In European telecommunications systems, all of these different functions may be combined into one node.
The SS7 network carries a great deal of information and is extremely critical to the operation of the phone system. If an SS7 network is not functioning, or if portions of it are not operating, the phone system simply cannot deliver phone calls, even though all of the voice circuits are operating properly. The capacity and complexity of the SS7 network is small in terms of circuitry and bandwidth utilized by an end user compared to previous voice and data networks. The circuitry of the SS7 network is therefore much more critical. The actual elements in the SS7 network do not provide all the information required in network operations to manage and to determine the health and state of an SS7 network. It is therefore necessary for the telephone industry to deploy surveillance equipment to monitor the links connecting the nodes of the SS7 network.
The topology of the network is such that STPs are typically deployed in a mated pair configuration at geographically separate locations. Connected to a mated pair of STPs will be a set of SSPs and SCPs. This conglomeration of SSPs, SCPs and mated Pair STPs is called a cluster. Clusters are then connected by D-Quad links between STP mated pairs. The mated pair configuration system is not required and it is not used in all communications systems capable of employing the present invention.
When any call, transaction or message is sent between two different devices on the network, it is often the case that the messages going from switch A to switch B travel one route on the network while the messages going from switch B to switch A travel a different route. The network surveillance equipment that monitors the link is designed to capture and correlate as much signaling information as possible regardless of network activity. Because of the different data paths that messages may take, it is difficult to do this correlation above what is called the transport layer when monitoring links at the STP sites. An example of an application level problem would be where a subscriber has a problem getting his/her calls delivered. The telephone company may attempt to fix the problem by doing a trace of all data pertaining to that subscriber's phone number, but the data may not all be located at one point. The data may be all in one STP, or split in some fashion, partially in one STP and partially in the other STP of a mated pair, which may be in a different city many miles away.
These and other objects, features and technical advantages are achieved by a system and method in which a monitoring network, having network monitors that capture messages, such as message signal units (MSUs), from links in a communications network, correlates the messages into call or transaction records for further processing. The monitors have a plurality of processors for processing the captured messages. The processors may run any of a number of message or record processing applications. In the present invention, a quality assurance application provides an integrated platform for message tracking on a per customer and/or a per service provider basis. The tracked messages may be part of one of a number of message protocols, such as Integrated Services Digital Network—User Part (ISUP), Telephone User Part (TUP), Network User Part (TUP), Transaction Capabilities Application Part (TCAP), Advanced Intelligent Network (AIN) or Integrated Network Application Part (INAP) calls or transactions. The quality assurance application is ideal for larger networks or for evaluating service quality of application-layer services, such as INAP, Global System for Mobile Communications (GSM), AIN, IS-41 and 800LIDB/CLASS.
In a preferred embodiment, the quality assurance application runs on a server that is external to the network monitoring system. The monitoring system provides data to the external server in the form of Call Detail Records (CDRs). The quality assurance application tracks the quality of service that is provided to customers on a particular communications network. The present invention allows customers, service providers and others to monitor how a service is performing not only within the network infrastructure, but also how well that service is working on a call-by-call, customer-by-customer basis. Additionally, the present invention allows service providers to efficiently manage network services without requiring an increased support staff.
The quality assurance application runs on an independent server and processes CDRs that are received from the monitoring system. In a preferred embodiment, individual monitoring units exchange and correlate messages into call or transaction records. The monitoring unit then filters the records using a CDR profile to determine which records, and which messages, should be combined to form the CDR. The monitoring units then transmit the CDRs directly to the external server. In an alternative embodiment, some other entity in the monitoring system, such as a central server, may generate and forward CDRs to the independent quality assurance application.
The quality assurance application provides service quality analysis tools and reports. The application generates historical statistic reporting for circuit-based services or for application-layer services. The statistics are maintained in a database which can be accessed to generate quality of service reports. When used to monitor service on an SS7 network, the present invention maintains statistics for all ISUP/TUP circuit-based calls. Statistics are maintained by called number, calling number and translated number. Users may generate reports for the statistical information by accessing the database through a workstation. The reports may be customized using various indices, such as by called, calling, or translated number.
Additional statistics may be monitored and other reports may be created for other communications networks or protocols. For example, TCAP statistics may be monitored and reports may be generated by service as well as by called, calling and translated number. Statistics for other application layer services could also be monitored. Such as for INAP, GSM, AIN, IS-41 and 800/LIDB/CLASS services.
Communications network monitoring equipment which may be used in conjunction with the present invention is disclosed in U.S. Pat. No. 5,592,530, entitled TELEPHONE SWITCH DUAL MONITORS; and in pending patent applications assigned Ser. No. 09/057,940, entitled SYSTEM AND METHOD FOR MONITORING PERFORMANCE STATISTICS IN A COMMUNICATIONS NETWORK; Ser. No. 09/092,428 entitled SYSTEM AND METHOD FOR DETECTING HIGH MESSAGE TRAFFIC LEVELS IN A COMMUNICATIONS NETWORK; Ser. No. 09/092,699 entitled SYSTEM AND METHOD FOR SIGNAL UNIT DATA STORAGE AND POST CAPTURE CALL TRACE IN A COMMUNICATIONS NETWORK; Ser. No. 09/092,256 entitled SYSTEM AND METHOD FOR GENERATING QUALITY OF SERVICE STATISTICS FOR AN INTERNATIONAL COMMUNICATIONS NETWORK; and Ser. No. 09/092,771 entitled SYSTEM AND METHOD FOR CORRELATING TRANSACTION MESSAGES IN A COMMUNICATIONS NETWORK, filed Jun. 5, 1998 the disclosures of which are hereby incorporated by reference herein. These references and the present application are commonly assigned.
It is a feature of the present invention to track performance statistics in a communications network. The invention provides statistical reports which show how many calls were successfully connected to the called number and how many calls were dropped. The reports allow users to determine the reason for call failures and to identify portions of the network which are not operating properly.
It is another feature of the present invention to allow customers, service providers and third parties with the ability to monitor a the quality of service on a particular communications network. Customers can use the statistical reports to determine their service provider's quality of service. The present system can also be used by customers to determine if the customers' systems are providing adequate service. For example, call centers can use the statistical data to determine whether additional agents are needed to answer calls that have been dropped due to busy lines. Service providers may use the information to monitor the service provided by their network and to identify failure points on the network. Service providers can also monitor the quality of service provided by other service providers on other networks.
It is an additional feature of the invention to generate statistical reports for called, calling or translated numbers or for services. Additionally, users can designate particular link sets to be used for the statistical report generation. As a result, only those monitors capturing messages from the designated link sets will send CDRs to the quality of service application.
It is another feature of the present invention to provide statistical reports in real-time on a network-wide basis for both calls and transactions. Historical data is also stored to a database for later recall by the user.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
Typically, a series of signals that are related to one call or transaction will traverse across the same path through network
In certain circumstances, such as for an 800 number call or for a call to an exchange or number that has been ported to a different switch, message may be sent to SCP
In network
Monitors
Server
In the present invention, monitors
Server
TABLE 1 is a list of the parameters that can be used to create CDR profiles.
| TABLE 1 | |
| Call State that Triggers the CDR Generation | |
| Address Complete | |
| Answer | |
| Call Termination | |
| Application Type | |
| ANSI ISUP | |
| ITU ISUP | |
| ITU TUP | |
| ITU NUP<$1 tr> | |
| LIDB | |
| AIN | |
| INAP | |
| National Variants | |
| Toll Free/800 | |
| Point Codes | |
| OPC | |
| DPC | |
| Calling Party Numbers | |
| Called Party Numbers | |
| Translated Numbers | |
| Dialed Digits | |
| Destination Digits | |
| Mobile Identification Number (MIN) | |
| Routing Numbers | |
| Account Numbers | |
| Electronic Serial Number | |
| Location Routing Number | |
TABLE 2 lists the fields of a preferred CDR format and the definitions of the field contents.
| TABLE 2 | ||
| Length of Entire CDR | ||
| Length of Fixed Fields | Indicates the length of the fixed CDR | |
| fields. The value is the number of bytes | ||
| after the “Length of Fixed” field to the | ||
| “User Field Length” field. | ||
| CDR Sequence Number | Numeric value that uniquely identifies | |
| the call record within the monitoring | ||
| system. Uniqueness is guaranteed | ||
| system wide. The system also uses this | ||
| number to indicate the delivery monitor | ||
| and its process ID. | ||
| CDR Condition Indicator | Indicates various conditions within a<$1 Time of Transaction Start | GMT time when a transaction begins. |
| Date/Time of Transaction End | GMT time, when a transaction end | |
| message is encountered. | ||
| CIC | Carrier Identification Code | |
| OPC | Network indicator, protocol as well the | |
| origination pointcode of the call. | ||
| DPC | Network indicator, protocol as well the | |
| destination pointcode of the call. | ||
| Abort Reason | Abort cause of the transaction. | |
| Application | SSN of the concerned application. | |
| Number of Calling Party Digits | The number of digits in the calling | |
| party number. | ||
| Calling Party Number | The phone number identified as the | |
| calling phone number. | ||
| Number of Called Party Digits | The number of digits in the called party | |
| number. | ||
| Called Party Number | The phone number identified as the | |
| called phone number. | ||
TABLE 3 lists the user defined fields of a preferred CDR format and the definitions of the field contents.
| TABLE 3 | |
| User Fields Length | Indicates the length of the user-defined CDR |
| fields section. The value is the number of bytes | |
| after this field to the end of the user defined | |
| fields. | |
| MSU Filds Length | Indicates the total length of the MSU section. |
| The value is the number of bytes after this field | |
| to the end of the CDR. | |
| Number of MSUs | Indicate the total number of the MSUs in this |
| CDR. | |
| Time Stamp | GMT time, when this transaction was |
| encountered. | |
| Link Number | Indicates the link identifier on which the MSU |
| was encountered. | |
| MSU Length | Indicates the total length of the MSU following. |
| MSU | Actual MSU that was captured by the |
| monitoring system. | |
Table 4 lists the fields for a CDR format with Integrated Services Digital Network-User Part (ISUP) parameters.
| TABLE 4 | |
| RIN Parameter | |
| UUI Octets | |
| USR Messages | |
| UUI Indicator | |
| Calling Party Nature of Address | |
| Redirecting Number Nature of Address | |
| Original Called Number Nature of Address | |
| Location Number Nature of Address | |
| Redirection Information | |
| TMR Value | |
| Calling Party's Category | |
| Number of Redirecting Number Digits | |
| Redirecting Number | |
| Number of Original Called Digits | |
| Original Called Number | |
| Number of Location Number Digits | |
| Location Number | |
| User Definable Parameters | |
Monitor
Typically, the CDRs are not stored on monitor
Monitoring system server
Users configure the QA CDR profiles, and other monitoring system parameters, using workstation
QA server
Depending upon the user's system, databases
The amount of data stored and the message traffic volume are the key determinants of the size and processing power of QA server
QA server
The format used to store the statistics data in database
Table 5 is a list of statistics that are stored to database
| TABLE 5 | |
| Number of Call Attempts | |
| Number of Call Attempts Answered | |
| Number of User Busy Calls | |
| Number of Ring No Answer (RNA) Calls | |
| Number of Normal Release Calls | |
| Number of Abnormal Release Calls | |
| Number of Unallocated Number Calls | |
| Number of Address Incomplete Calls | |
| Number of Transaction Aborts | |
| Number of Congested Transactions | |
| Number of Congested Calls | |
| Number of Circuit Unavailable Calls | |
| Number of Failed Transactions | |
| Number of Failed Calls | |
| Number of Undefined Release Cause Failed Calls | |
| Number of Destination Out of Order Failed Calls | |
| Average Call Set-Up Time | |
| Average Call Hold Time | |
| Average Answer Seizure Ratio | |
| User Defined | |
The user can define specific statistics, such as release causes, that are to be stored for a particular CDR profile.
Table 6 is a list of aggregations that can be used to group the above statistics for reports to be generated by QA report application
| TABLE 6 | |
| Calling Numbers | |
| Called Numbers | |
| Translated Numbers | |
| Called Numbers, then by Calling Numbers | |
| Translated Numbers, then by Calling Numbers | |
| Called Numbers, then by Translated Numbers | |
| Services | |
| Services, then by Calling Numbers | |
| Services, then by Called Numbers | |
In Table 6 it will be understood that called, calling or translated numbers may be either a complete telephone number or a partial telephone number. For example, under the North American Numbering Plan, reports may be created for fall telephone numbers (i.e. 1-NPA-NXX-XXXX). Alternatively, wildcards can be used at the end of the grouping telephone number so that statistics are reported for all calls or transactions directed to a particular area code (i.e. 1-NPA) or a particular exchange code (i.e. 1-NPA-NXX.
Users can also configure QA report application
Dynamic behavioral statistics may also be generated by QA report application
Users may track statistical events by designating a statistics to be displayed based upon a first occurrence, a occurrence that is more than some delta away from a certain value, or rising/falling thresholds. When triggered, events may be displayed to the user, or stored to a log file.
Users may also designate specific link sets or network nodes to be used for the statistical reports. Only those monitors that are coupled to the relevant links and nodes will receive the CDR profile data and only those monitors will send CDRs to QA server
Real-time statistics are also available from QA report application
It will be understood that workstation
It will also be understood that the QA server can accept CDR data from any source, not only from the monitoring system. For example, a switch or end office may generate CDRs and provide the data directly to the QA server for further processing. The QA server has a modularized front end which allows it to receive data from any source.
Although the invention has been described with respect to an SS7 system, it will be understood that the present invention may be adapted to monitor the quality of service provided on any communications network.
The present invention and its advantages have been described in detail herein, however, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.